Dying identical doctors and a shape-shifting alien assassin draw Mulder and Scully into a clone conspiracy, entangled with the sudden reappearance of Mulder's long-lost sister.
First aired: 1995-02-10
Director
Nick Marck
Writers
David Duchovny, Chris Carter
Guest cast
Mitch Pileggi, Brian Thompson, Peter Donat, Megan Leitch, Dana Gladstone, Tom Butler, Rebecca Toolan, Andrew Johnston, Bonnie Hay, Tim Henry, Ken Roberts, Michael Rogers, David L. Gordon, Richard Sargent, Linden Banks, Oliver Becker, James Leard, Kim Restell